Gas turbine engines may comprise cases surrounding components such as a compressor case. In various embodiments, components of case may be coupled to each other at mating flanges. Relatively hot air may flow inside the case and relatively cool air may flow outside the case tending to induce a thermal gradient between the inner diameter of the case and the outer diameter of the case and between the mating flanges. In various embodiments, the thermal gradient tends to induce stresses within the case and the mating flanges tending thereby to reduce component lifetime.